Wei Li Ong

Solar energy can be harnessed and converted into heat via the photothermal effect, which can then be utilized to drive many other reactions to produce important resources, such as water, fuel, electricity, and even mechanical actuation in a clean and sustainable manner. Hydrogels and membranes coupled with photothermal materials are particularly suitable for this purpose because they possess advantageous properties, such as porosity and adaptability. These properties allow for the introduction of diverse additives and functionalities, ensuring that photothermal systems can be customized for specific tasks, thereby enhancing their overall performance, functionality and versatility. This review aims to provide an overview of recent developments and the significance of employing photothermal hydrogels and membranes in multiple fields ranging from clean water, fuel production, electricity generation to mechanical actuation, followed by a discussion on key considerations in materials design and engineering. Finally, the review addresses the challenges and future directions of photothermal applications.

A facile approach for achieving homogenous Cu embedment in TiO ₂ for an exceptionally high and stable H ₂ production rate.

Currently, the production of hierarchical 2 D layered carbon is mostly limited by low yields, laborious processing, and the high tendency for reaggregation. Hence, it is still a challenge to attain stable porous carbon structures with a well‐preserved layered structure and hierarchical pores. Here, we demonstrate a facile and simultaneous activation–exfoliation–reassembly technique to perform structural modification and pore tailoring of carbonaceous matrices conveniently. Various pore creations can be realized concurrently from in‐plane micro‐/mesopores by chemical activation, expansion of intersheet mesopores, and interconnectivity of the layered structure to form 3 D macropores. Finally, a proof‐of‐concept demonstration of the combination of hierarchical macro‐/micro‐/mesoporous layered carbon structure and TiO₂ nanosheets shows promising adsorption and catalytic properties.

Large‐area, 2D, anisotropic, direct growth of nanostructures is considered an effective and straightforward way to readily fulfill transparent, flexible technology requirements. In addition, formation of thin hybrid structures by combining with another 2D material brings about dimensional advantages, such as intimate heterostructure functionalities, large specific area, and optical transparency. Here, we demonstrate 2D planar growth of thin Ni(OH)₂ nanosheets on arbitrary rigid and soft supports, by exploiting the growth strategies of oriented attachment induced by interfacial chemistry and the intrinsic driving force of layered structure constitution. Moreover, large‐scale 2D heterohybrids have successfully been prepared by direct conformal growth of Ni(OH)₂ nanosheets overlying MoO₃ nanobelts. Unlike the exfoliation and transfer of 2D materials technique, this approach minimizes multiple process contamination and physical‐handling structural defects. Accordingly, proof‐of‐concept flexible electrochromism is demonstrated in view of its prerequisite to the access of a large homogeneous material coating. The as‐synthesized 2D layered structure affirms its optical and electrochemical superiority through the display of wide optical modulation, high coloration efficiency, good cyclic stability, and flexibility.

A solution-processable 2D hydrated layered structure, Ni(OH) ₂ nanosheets with hollow TiO ₂ nanosphere composite designed to deliver photocatalytic degradation coupled electrochromism for environmental and energy conservations.

This review aims to provide a comprehensive and contemporary overview, as well as a guide of the development of new generation TiO₂ based photocatalysts via structural design for improved solar energy conversion technologies.

Utilizing solar energy for environmental and energy remediations based on photocatalytic hydrogen (H₂) generation and water cleaning poses great challenges due to inadequate visible-light power conversion, high recombination rate, and intermittent availability of solar energy. Here, we report an energy-harvesting technology that utilizes multiple energy sources for development of sustainable operation of dual photocatalytic reactions. The fabricated hybrid cell combines energy harvesting from light and vibration to run a power-free photocatalytic process that exploits novel metal–semiconductor branched heterostructure (BHS) of its visible light absorption, high charge-separation efficiency, and piezoelectric properties to overcome the aforementioned challenges. The desirable characteristics of conductive flexible piezoelectrode in conjunction with pronounced light scattering of hierarchical structure originate intrinsically from the elaborate design yet facile synthesis of BHS. This self-powered photocatalysis system could potentially be used as H₂ generator and water treatment system to produce clean energy and water resources.